Today I have sent a little Ethereum to my address but it instantly transferred to another address. Later, I tried again sending 0.002 ETH and the same. It also transferred that same address instantly.
How to get solve this?
It is possible your wallet has been hacked, what i am sure about is that someone is sending from your recipient address to his or her own address it can't just auto send to another wallet your private key has been exposed to a third party. As it stands you should open a new wallet or buy adware wallet for better wallet security.